New Nonlinear Robust Control Method Based on the State Extending and Filtering Estimation

In this paper, the state extending and filtering robust control (SEFERC) is proposed and investigated. In the SEFERC, the uncertain nonlinear part of the MIMO is extend to the new state parameter and estimated by the nonlinear tracking filter. With the estimated value, by the direct feedback linearization (DFL) method and H∞ control method, the nonlinear system can be converted to the linear system and stabilized with the robust control theory. Taking the certain excitation and speed synthetic control system for example, simulation results show that the SEFERC can accelerate the convergence speed of the state variables and improve the excitation and speed control speed.